docs: def conjugate(self):
          """:obj:`DualQuaternion`: The conjugate of this quaternion.
          """
          qr_c_xyzw = quaternion_conjugate(self._qr)
          qd_c_xyzw = quaternion_conjugate(self._qd)
  
          qr_c_wxyz = np.roll(qr_c_xyzw, 1)
          qd_c_wxyz = np.roll(qd_c_xyzw, 1)
          return DualQuaternion(qr_c_wxyz, qd_c_wxyz)